A Demographic-Macroeconomic Model of the U.S. has been developed. The impact of population aging will be examined on the nation's economy, retirement income system, labor force, and the welfare of the aged. The demographic Macroeconomic Model represents the integration of eight models - Hudson-Jorgenson Growth Model, Anderson Labor Model, ICF Inc. Population Model, Social Security Model, Private and Public Employees Pension Model, Supplemental Security Income Model, and Medicare Model.